Chapter 8 Data Collection, Data Quality and the History of Cause-of-Death Classifi cation Vladimir Shkolnikov , France Meslé , and Jacques Vallin Until 1996, when INED published its work on trends in causes of death in Russia (Meslé et al . 1996 ) , there had been no overall study of cause-specifi c mortality for the Soviet Union as a whole or for any of its constituent republics. Yet at least since the 1920s, all the republics had had a modern system for registering causes of death, and the information gathered had been subject to routine statistical use at least since the 1950s. The fi rst reason for the gap in the literature was of course that, before perestroika, these data were not published systematically and, from 1974, had even been kept secret. A second reason was probably that researchers were often ques- tioning the data quality; however, no serious study has ever proved this. On the contrary, it seems to us that all these data offer a very rich resource for anyone attempting to track and understand cause-specifi c mortality trends in the countries of the former USSR – in our case, in Ukraine. Even so, a great deal of effort was required to trace, collect and computerize the various archived data deposits. This chapter will start with a brief description of the registration system and a quick summary of the diffi culties we encountered and the data collection methods we used. We shall then review the results of some studies that enabled us to assess the quality of the data. V. Shkolnikov (*) Max Planck Institute for Demographic Research , Konrad Zuse Strasse 1 , 18057 Rostock , Germany e-mail: [email protected] F. Meslé • J. Vallin Institut National d’Études Démographiques , Bd. Davout 133 , 75980 Paris Cedex 20 , France e-mail: [email protected] ; [email protected] F. Meslé and J. Vallin, Mortality and Causes of Death in 20th-Century Ukraine, 121 Demographic Research Monographs, DOI 10.1007/978-94-007-2433-4_8, © Springer Science+Business Media B.V. 2012 122 V. Shkolnikov et al. 8.1 The Registration and Coding System The history of cause-of-death statistics in Ukraine is a relatively short one. It was only in 1925 that a system for registering cause of death on a regular basis was instituted throughout Ukraine (and across the USSR). The fi rst Soviet Classifi cation of Causes of Death, drawn up in 1922 and offi cially adopted in 1924 (Sadvokasova 1955 ) , was quite close to the 1920 International Classifi cation of Diseases (ICD). However, full registration of causes of death was still not achieved, because doc- tors alone were empowered to write death certifi cates (Bystrova 1965 ) , and some places – notably rural areas 1 – had very few doctors. It was only in towns that the system functioned properly, covering less than half the population of Ukraine. The situation improved from 1958, when the Ministry of Health and the TsSU (Central Statistical Directorate of the Soviet Union) decided to authorize another category of medical worker, the feldsher , 2 to make out a death certifi cate when there was no doctor. In 1959, 15% of death certifi cates in rural areas were completed by a feldsher . The proportion then decreased steadily throughout the 1960s and 1970s, falling to 5% or 6% in the mid-1980s. Since most of the data we processed were compiled under the Soviet regime, we shall start by describing the system of registration and coding in force during that era. We shall go on to show that the change in political regime has not as yet called this system into question. 8.1.1 The Soviet System of Registering and Coding Causes of Death After a death, the deceased’s relatives must obtain a medical certifi cate of cause of death from the responsible institution (hospital, poliklinika [district clinic] or sudebno-meditsinskaia expertiza [Forensic Medical Examiner’s Offi ce]) and take it to the district register offi ce (ZAGS). They exchange it for a civil death certifi cate that serves as both a burial permit and a legal document for inheritance purposes. ZAGS then sends the medical death certifi cate to the regional offi ce of statistics (for the Oblast [province] or similar administrative area 3 ). As in most countries, the medical death certifi cate distinguishes three levels of causes: the underlying (principal or primary) cause, the immediate cause and contributory (associated or secondary) causes. Statistical tables are based on the 1 The archives contain no record of deaths by cause for rural areas before the early 1950s. 2 Within the Soviet health system, someone with an intermediate qualifi cation, between a midwife and a doctor. 3 Such as Autonomous Republic or Autonomous Territory. 8 Data Collection, Data Quality and the History of Cause-of-Death Classifi cation 123 Table 8.1 Cause-of-death Classifi cations in the USSR since the Second World War Period Title Number of items Age groups used 1955–1964 1952 classifi cation 116 0, 1, 2, 3–4, 5–6, 7–13, 14–15, (Soviet classifi cation 16–17, 18–19, 20–24, 25–29, of causes of death, 3rd 30–39, 40–49, 50–59, 60–69, revision) 70 and over 1965–1969 1965 classifi cation (based 210+13 a 0, 1, 2, 3, 4, 5–9, 10–14, …, 80-84, on ICD-7) 85 and over 1970–1980 1970 Classifi cation (based 185+10 a 0, 1, 2, 3, 4, 5–9, 10–14, …, 80-84, on ICD-8) 85 and over 1981–1987 1981 classifi cation (based 185+10 a 0, 1, 2, 3, 4, 5–9, 10–14, …, 80–84, on ICD-9) 85 and over Since 1988 b 1981 classifi cation, adapted 175+10 a 0, 1, 2, 3, 4, 5–9, 10–14, …, 80–84, for deaths from injury 85 and over and poisoning (based on ICD-9) a For classifying deaths from injury and poisoning according to nature of injury b The 1988 revision was modifi ed in the 1990s in order to identify previously non-existent causes (like AIDS) or causes that had not been recorded singly (such as hunger) underlying cause. In Ukraine, regional offi ces of statistics are responsible for coding the cause of death, and each one produces an annual table (‘Form No. 5’) giving the number of deaths by sex, age group and cause. These regional tables are then sent to be processed and totalled up centrally for the whole of Ukraine (as was the case for the other Soviet republics) by Goskomstat of Ukraine; until 1991, they were then processed at the level of the whole Soviet Union by Goskomstat of the USSR. These tables are the main source of the mortality data used in our study. The USSR never adopted the World Health Organization’s International Classifi cation of Diseases, Injuries and Causes of Death , but used its own classifi - cation, with a detailed list that, from 1965, included about 200 items. From the foundation of the Soviet state, seven different versions of this classifi cation were used in succession, fi ve of them after the Second World War. Table 8.1 gives an overview of the latter. The Ministry of Health and Goskomstat have had joint responsibility for modifi - cations 4 to the certifi cate of cause of death and to the rules on declaration and cod- ing, as well as for successive revisions of the Classifi cation. Goskomstat entirely computerized its processing of mortality data in 1988; until then, cross-tabulations had been produced manually. Four of these successive versions were in use between 1965 and the Independence of Ukraine: the 1965, 1970, 1981 an d 1988 Revisions. A detailed description of these is to be found in Annex III on the Website ( http://www.demogr.mpg.de/books/ drm/009 o r http://extras.springer.com/ ) . 4 To our knowledge, new directives were introduced at least eight times – in 1954, 1964, 1966, 1980, 1984, 1986, 1989 and 1992. 124 V. Shkolnikov et al. Three particular features of the Soviet system for declaring and recording cause of death are worth emphasizing. 1. The Soviet Classifi cation has always differed signifi cantly from the ICD defi ni- tions, although they were brought somewhat closer together from 1965 onwards. In particular, the number of Soviet items is far smaller than the number of ICD items: 210 items in 1965–1969, as against over 2,000 in ICD-7; from 1970, 185 instead of almost 3,000 in ICD-8 and then over 5,000 in ICD-9 (WHO 1977 , 1978 ). Goskomstat produced a special document with a table showing correspondences between the 1981 Soviet Classifi cation and ICD-9 (Goskomstat 1981 ) . 2. Up to 1988, some items in the Soviet Classifi cation did not appear in the ordinary annual tables of statistics (‘Form No. 5’): these causes (cholera, plague, suicide, homicide and occupational accidents) were concealed for political reasons. In order to ensure consistent “All causes” totals, the deaths attributed to these ‘ hidden’ causes were added to the “Ill-defi ned causes of death”. In fact, the hid- den causes were also accounted for separately in a special, top-secret table (‘Form No. 5b’), which we were fi nally able to consult for the years 1963–1982 and 1984–1987 – though not for 1983. However, we were able to subject that year to an indirect estimate from the data available for the whole USSR and from the special category reserved for deaths from injury and poisoning. 5 There is no mystery as to why the Soviet authorities kept these causes secret: in 1970, for example, the standardized male mortality rate from homicide in the Soviet Union was almost eight times the European average.